Forty years ago, the Democratic Party stopped being a democratic party. Race and sex, rather than votes, determined who determined the party’s nominee at its 1972 convention. That the most egregious instance of quotas trumping the will of voters involved the Illinois delegation underscores the convention’s repercussions on our current polarized politics.

Barack Obama four years ago, like George McGovern forty years ago, waged an antiwar campaign against a more establishment Democrat associated with that war. The senator from Illinois, like the senator from South Dakota, was his party’s second-leading vote-getter during the primary season. Both 2008 and 1972 were strangely dubbed watershed years for democratizing the political process. Yet Hillary Clinton in 2008, like Hubert Humphrey in 1972, won the popular vote during the primaries only to lose the delegate count during the Democratic National Convention. Meet the new party bosses, same as the old party bosses.

The seeds of victory for the two most radical nominees in major-party history were sown by rules imposed as a result of 1968’s tumultuous convention. In response to the Windy City’s convention commotion, a committee chaired by George McGovern made it easier for the rioters outside the gathering in 1968 to influence the party inside the gathering in 1972 and beyond. That they did. Outside the ill-fated Chicago convention, Bill Ayers targeted policemen with marbles fired from his slingshot and Tom Hayden got arrested for deflating a squad car’s tire. The former subsequently served with Barack Obama on numerous Chicago-area boards and the latter was one of the four founders behind Progressives for Obama. Other radicals in the Second City’s streets included Mike Klonsky, who blogged on an Obama campaign’s website, Carl Davidson, who organized the event where Obama first publicly spoke against the Iraq War, and Bernardine Dohrn, who hosted the first fundraiser of Obama’s political career along with her husband Bill Ayers. The mob rules.

For a sign of the symbolic, and substantive, changing of the guard, the example of Richard J. Daley, who opened the 1968 convention and was stripped of his credentials at the 1972 convention, suffices. The Chicago mayor’s Cook County slate won election as delegates to 1972’s Democratic National Convention. But in Miami, the convention recognized a slate led by Jesse Jackson, who hadn’t even cast a ballot in Illinois’ Democratic primary. The 59 Daley-led delegates had won their place at the convention via the voters of Cook County. But the credentials committee found the victorious slate lacking in women and minorities. So, duly elected delegates were replaced with ones who had been defeated or had never appeared on ballots in the first place. The forces of George McGovern invoked a quota rule devised by the McGovern Commission to disqualify delegates hostile to George McGovern.

“There won’t be any riots in Miami because the people who rioted in Chicago are on the Platform Committee,” writer Ben Wattenberg quipped. Indeed, the Democrats crafted a platform aimed more at provoking Middle America than at winning them over. The document called for prisoners’ rights, federal funding for local food cooperatives, the adoption of an Ethnic Studies curriculum bill, and for the public to “refrain from buying or eating non-union lettuce.”

Were these the demands of a national political party or a splinter group holed up in the student union?

The riotous behavior outside in Chicago moved indoors in Miami. Under McGovern Commission rules, activists playfully nominated for vice president migrant-worker organizer Cesar Chavez, Yippee Jerry Rubin, anti-corporate crusader Ralph Nader, Communist dictator Mao Zedong, and sitcom character Archie Bunker. The joke was on them. The not-ready-for-primetime convention pushed its nominee’s acceptance speech to 2:48 a.m. Eastern time, too late for the morning papers but peak viewing hours for a ten-year-old boy in Honolulu. McGovern began his acceptance speech by joking, “I assume that everyone here is impressed with my control of this Convention that my choice for vice president was challenged by only 39 other nominees.” But the chaos reflected his control in that the commission he had chaired enabled the pranksters to derail the process.

Whereas the former law professor promised “hope” and “change,” the history professor pledged “hopeful change” in his acceptance speech. McGovern, a veteran of the Henry Wallace presidential campaign influenced by the writings of Owen Lattimore, and Obama, an Alisnkyite organizer during his twenties, both emphasized America’s defects and “change” as a panacea. Just as Democrats advanced a “fifty-state strategy” in 2008, McGovern told the throngs, “We’re not conceding a single state to Richard Nixon.” But Nixon ultimately conceded just one state to McGovern—hence the ubiquitous Watergate-era bumper-sticker: “Don’t blame me—I’m from Massachusetts.” America wasn’t ready for George McGovern in 1972. They were in 2008.

McGovern recalled, “I opened the doors of the Democratic Party and 20 million people walked out.” But a smaller party, with fewer of those pesky Southerners and blue-collar workers, proved easier to co-opt than those diverse coalitions that had elected Democratic presidents to sit in the White House for 28 of 36 years between 1932 and 1968. George McGovern lost an election. He created a party.

The quota system he implemented still reigns. Dividing America into groups, not uniting them in one big group, was McGovern’s forte—and Obama’s too. The Democratic Party of California, for instance, which had made the wrong kind of news in 1972 when almost one in five of its delegates was on welfare, this year calls for an equal division between male and female convention proxies, and for a delegation 16 percent African American, 29 percent Hispanic, 12 percent lesbian, gay, bisexual, and transgender, and ten percent handicapped to achieve “a representative balance.”

The mania for representation leaves many traditional Democrats without much representation. “All pretense of trying to win a majority of the white working class has been effectively jettisoned,” Thomas Edsall reported in the New York Times late last year. In its place, Obama’s reelection campaign will forge “a center-left coalition made up, on the one hand, of voters who have gotten ahead on the basis of educational attainment—professors, artists, designers, editors, human resources managers, lawyers, librarians, social workers, teachers and therapists—and a second, substantial constituency of lower-income voters who are disproportionately African-American and Hispanic.” What was once the party’s base is now a constituency that goes uncourted.